The invention relates to apparatus for manipulating elongated webs which contain a photosensitive material and are to be processed in a laboratory wherein they advance first through a developing unit and thereupon through a copying unit. More particularly, the invention relates to improvements in apparatus which can be utilized with advantage for the development and copying of exposed photographic customer films in a processing laboratory.
Many amateur photographers, as well as numerous professionals, often desire to obtain developed photographic films, together with prints of all or selected exposed and developed film frames, without much delay. This has given rise to rapid spreading of establishments which specialize in instant service, e.g., in development, copying and printing of customer films within sixty minutes from the time of receipt of developed photographic films. Such establishments can be found in all or nearly all major cities as well as in numerous tourist centers, pilgrims' centers and even medium sized and smaller towns.
As a rule, an establishment which specializes in instant service will employ two machines, namely a developing unit for exposed photographic films and a miniature laboratory wherein a copying unit is combined with a developing unit for exposed photographic paper. Many establishments are set up in such a way that they can process wider or narrower exposed films as well as make smaller or larger prints on photographic paper or other suitable photosensitive material. Thus, it is already known to employ so-called leaders which are designed to be transported through a film developing unit and can entrain discrete films or plural films of various widths and/or lengths. The formats of all leaders are the same; this ensures that one and the same conveyor system can advance the leaders through the film developing machine irrespective of the number and or types of films which are being entrained by the leaders. The leaders are made of a material which can stand the corrosive and/or other influences of various baths in a film developing unit as well as the heating action in a dryer which normally follows the last bath in the developing unit. Reference may be had to U.S. Pat. No. 4,613,222 granted Sep. 23, 1986 to Takase et al. for "Film accumulating device for developing apparatus".
Attempts to further simplify and reduce the cost of processing of exposed films in an establishment specializing in instant service include the proposal to employ a single machine which can perform the film developing, copying and paper developing operations. In accordance with this proposal (reference may be had to U.S. Pat. No. 4,864,354 granted Sep. 5, 1989 to Crasnianski for "Integrated automatic machine for simultaneously and continuously effecting the development of photographic films and the printing and development of photographic prints"), the single machine employs a film developing unit which does not utilize any leaders. This simplifies the manipulation of films and the making of prints in certain ways but detracts from the versatility because the film transporting mechanism is designed to advance only films of a particular type, e.g., the popular 135 roll films. Consequently, establishments which employ machines of the type disclosed by Crasnianski can accept only one format of films for one-hour service.